Answer:
multiply divide and count
Each of ENIAC's 20 accumulators could do 5000 additions or subtractions per second. A special panel called the "multiplier" could control 4 accumulators to do multiplication by repeated addition and shifting. A special panel called the "divider/square rooter" could control 5 accumulators to do division by repeated subtraction and shifting or square roots using a modification of the division process. A special panel called the "master programmer" could be programmed to sequence the machine through arbitrary functions or iterative processes.